1. Technical Field
The present invention relates to power management in general, and in particular to power management for computer systems. Still more particularly, the present invention relates to a method for managing power consumption of multiple computer servers.
2. Description of the Related Art
Concerns over excess power consumption are no longer confined to specialized computer systems, such as computer systems specifically designed to be used in aerospace environment, but also expand to general-purpose computer systems as well. The ability of computer servers to support the high demands of present-day workloads, especially in the realm of electronic commerce and web-hosting industry, is limited by the inability of the computer servers in facilitating power consumption and heat dissipation problems. The heat dissipation problem is attributed to the large number of computer servers enclosed in a relatively small space, and the power consumption problem is attributed to the high number of high-performance processors within those computer servers. For example, a modern-day computer server complex designed for electronic commerce and web-hosting applications typically constitutes thousands of computer servers operated in parallel, occupying thousands of square footage of computer room space, with each computer server consuming many watts of power.
In certain applications, low-power processors may be a simple solution to the above-mentioned problems. However, it is safe to say that a new market-acceptable price-power-performance equilibrium has yet to be demonstrated in the computer server market, and, in fact, the performance limitations of low-power processors may limit their ultimate penetration into such market. In addition, processor power consumption, while significant, does not account for all the power consumed by a computer server. Memory controllers, adapters, disk drives, and other peripheral devices account for a large fraction of the power consumption of a computer server, and cannot be neglected.
Consequently, it would be desirable to provide an improved method for managing the power consumption of computer servers.
In accordance with a preferred embodiment of the present invention, the current workload information and the current capacity information of a group of computer servers within a computer server pool are determined. A short term history and a long term history of the workload information are then built based on the determined workload information. Next, the information regarding short-term variations in workload is determined. Similarly, the information regarding long-term variations in workload is determined. Based on a combination of the above-mentioned determined short-term and long-term information, at least one of the computer servers is powered on or powered off.
All objects, features, and advantages of the present invention will become apparent in the following detailed written description.